Method of controlling a movement of a door with a controllable rotary damper

ABSTRACT

A door component has a controllable rotary damper and two connector units which can be moved relative to one another. One of the two connector units can be connected to a load-bearing construction and the other one can be connected to a movable door device of a vehicle, in order to damp a movement of the door device between a closed position and an open position in a controlled manner. Two mutually engaged spindle units are arranged between the two connector units, one spindle unit being a threaded spindle and the other being a spindle nut. A first spindle unit is fastened rotatably on a coupling rod connected to one of the connector units. A magnetorheological transmission device is arranged between the coupling rod and the first spindle unit, in order to brake a rotational movement of the first spindle unit as required.

CROSS-REFERENCE TO RELATED APPLICATION

This is a continuation application of U.S. patent application Ser. No.16/615,291, filed Nov. 20, 2019, which was a § 371 national stage ofInternational Patent Application PCT/EP2018/063114, filed May 18, 2018;the application also claims the priority, under 35 U.S.C. § 119, ofGerman Patent Application DE 10 2017 111 032.1, filed May 20, 2017; theprior applications are herewith incorporated by reference in theirentirety.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to an apparatus having a controllablerotary damper which comprises at least one magnetorheologicaltransmission apparatus, and to a method.

A rotary damper having a magnetorheological fluid can be used in anadvantageous manner. Magnetorheological fluids have, for example, veryfine ferromagnetic particles, such as for example carbonyl iron powder,distributed in an oil. In magnetorheological liquids, use is made ofspherical particles with a diameter of one to 10 micrometers owing to aproduction process, wherein the particle size is not uniform. If amagnetic field is applied to such a magnetorheological fluid, then thecarbonyl iron particles of the magnetorheological fluid catenate alongthe magnetic field lines, such that the rheological characteristics ofthe magnetorheological fluid (MRF) are significantly influenced in amanner dependent on the form and intensity of the magnetic field.

Hitherto known apparatuses with a controllable rotary damper are oftenof complex design in order to satisfy the set requirements. Therefore,such apparatuses are not cheap to produce. Another difficulty here isfor example that door dampers for motor vehicles and passenger carscompete with mechanical door arresters, which are produced millionfoldand which are therefore optimized and inexpensive and which arrest anautomobile door in two or three different angular positions.

BRIEF SUMMARY OF THE INVENTION

It is therefore the object of the present invention to provide animproved and/or less-expensive apparatus with a controllable rotarydamper based on magnetorheological action.

The object is achieved by means of an apparatus and a method as claimed.Preferred refinements of the invention are the subject of the dependentclaims. Further advantages and features of the present invention willemerge from the general description and from the description of theexemplary embodiments.

A first apparatus according to the invention is designed as a damperdevice and comprises two attachment units which are movable relative toone another and a controllable rotary damper in order to dampen arelative movement of the attachment units with respect to one another incontrolled fashion. Between the two attachment units, are there arearranged two spindle units which are in engagement with one another,wherein one spindle unit is designed as a threaded spindle and the otherspindle unit is designed as a spindle nut. A first spindle unit (and inparticular the threaded spindle) is fastened rotatably on a coupling rodwhich is connected (indirectly or directly) to one of the attachmentunits. A magnetorheological transmission apparatus is arranged betweenthe coupling rod and the first spindle unit (in particular the threadedspindle) in order to influence (and in particular brake) a rotationalmovement of the first spindle unit (as required).

Such an apparatus can be used in an advantageous and versatile manner indifferent technical fields (prosthetics, doors of buildings, doors ofcupboards (for example in a kitchen) or items of furniture . . . ).

Another apparatus according to the invention is designed as a doorcomponent and has at least one controllable rotary damper and twoattachment units which are movable relative to one another, wherein oneof the two attachment units is connectable to a supporting structure andthe other of the two attachment units is connectable to a movable doordevice, in particular of a (motor) vehicle, in order to dampen amovement of the door device at least partially between a closed positionand an open position in controlled fashion.

Two spindle units which are in engagement with one another are arrangedbetween the two attachment units, wherein one spindle unit is designedas a threaded spindle and the other spindle unit is designed as aspindle nut. A first spindle unit (and in particular the threadedspindle) is fastened rotatably on a coupling rod connected to one of theattachment units. A magnetorheological transmission apparatus isarranged between the coupling rod and the first spindle unit in order toinfluence (and in particular brake) a rotational movement of the firstspindle unit (in particular of the threaded spindle) (as required).

Said apparatus according to the invention is highly advantageous and canbe used for example for damping a movement of an automobile door or of atailgate or front hood etc., such that pivoting movements of doors aboutvertical and/or horizontal axes are possible.

In preferred refinements of all devices described above, the spindleunits convert a linear movement of the attachment units relative to oneanother into a rotational movement of the spindle units with respect toone another.

Preferably, in the event of a relative movement of the attachment unitswith respect to one another, a relative axial position of the spindleunits (of spindle nut and threaded spindle) with respect to one anotherchanges.

In particular, the first spindle unit is designed as a threaded spindleand/or, preferably, the second spindle unit is designed as a threadednut.

It is preferable if the spindle nut radially surrounds the threadedspindle.

In particular, the threaded spindle is designed to be at least 30%, andpreferably 40% or 50%, longer than the spindle nut.

It is preferable if the magnetorheological transmission apparatus isarranged radially within the first spindle unit (and in particular thethreaded spindle).

In all embodiments, it is preferable if the threaded spindle isrotatable relative to the spindle nut and relative to the coupling rod.

It is advantageous if an annular cylindrical cavity is formed radiallybetween the coupling rod and the first spindle unit.

Preferably, a cylindrical sleeve composed of a magnetically conductivematerial is received in the first spindle unit and is connectedrotationally conjointly to the first spindle unit.

Preferably, the cavity is filled with a magnetorheological medium.

It is advantageous if the first spindle unit (threaded spindle) iscomposed at least partially (or almost entirely, or entirely) of aplastic. This saves weight. Self-lubrication can also be achieved.

In particular, the magnetorheological transmission apparatus comprisesat least one electrical coil and in particular a multiplicity ofelectrical coils.

Preferably, the electrical coil has windings wound around the couplingrod.

Preferably, the magnetorheological transmission apparatus comprises atleast one magnetic circuit which comprises an axial portion in thecoupling rod, an axial portion in the cylindrical sleeve and/or thefirst spindle unit (in particular threaded spindle), the electrical coiland, on at least one axial side of the electrical coil, at least onerotary body which is arranged in the radial gap between the coupling rodand the first spindle unit (preferably threaded spindle).

It is preferable if in each case at least one rotary body is arranged onboth axial sides of the electrical coil.

In particular, a multiplicity of rotary bodies is arranged, on at leastone axial side of the electrical coil, so as to be distributed over thecircumference of the coupling rod.

In particular, the (or at least one) magnetic circuit comprises, on bothaxial sides of the electrical coil, rotary bodies arranged in the radialgap between the coupling rod and the threaded spindle.

Preferably, a multiplicity of magnetic circuits are formed.

It is preferable if at least one electrical cable such as a connectioncable for the electrical coil is led through a channel in the couplingrod. The leadthrough of cables for sensors is also possible. A cable mayalso be led out at both ends or sides. Thus, in a usage situation on anautomobile door, for example on the one hand in the direction of thedoor pillar or also into the inner part of the door.

Preferably, the coupling rod is pivotable about a pivot axle orientedtransversely with respect to the coupling rod.

In particular, the first spindle unit (threaded spindle) is received inan axially fixed manner on the coupling rod.

In particular, the first spindle unit extends over the axial adjustmentrange.

It is preferable if a motor for driving the first spindle unit isincluded.

The method according to the invention serves for influencing a movementof a door device with a door component having at least one controllabledamper device and having two attachment units which are movable relativeto one another, wherein two spindle units which are in engagement withone another are arranged between the two attachment units. A movement ofthe door device at least partially between a closed position and an openposition is controlled. Here, the damper device and/or a motor fordriving one of the spindle units is controlled in order to achieve aguided door movement.

In particular, the method serves for influencing a door movement of adoor device having an above-described door component with a damperdevice.

In a preferred embodiment of the method, the method serves forinfluencing a door movement of a door device having an above-describeddoor component with a damper device. Here, the door component comprisesin particular one or preferably a first and a second spindle unit andpreferably at least one motor for driving the first spindle unit. Themotor, designed in particular as an electric motor, and the damperdevice are interconnected such that a haptically advantageous guideddoor movement is made possible.

In refinements of the method or of the methods, features as describedabove are present.

Comments will be given below regarding the construction, the functionand the method of implementation:

Magnetic circuit: a magnetic circuit forms around any coil. The magneticcircuit is closed in particular via the two (adjacent) rolling bodies,the coupling rod and a sleeve (tube). All parts of the magnetic circuitare particularly preferably ferromagnetic; the magnetic characteristicsare normally of lesser importance in the case of the other parts. Onlythose parts which would otherwise cause a “magnetic short circuit”, thatis to say a secondary path for the magnetic field past the rollingbodies (such as in particular the ball bearing or deep-groove ballbearing, the holder of the sealing ring or of the shaft sealing ring anda stop ring) must be non-ferromagnetic.

The sleeve bears against the inside of the threaded spindle. The sleeveis not necessary if the threaded spindle itself is ferromagnetic. Owingto the sleeve, however, the threaded spindle does not requireferromagnetic characteristics and can be entirely optimized for goodsliding characteristics/cheap production/service life.

In the case of the construction illustrated in the exemplary embodiment,multiple preferably coil/rolling body assemblies are used. Theconstruction analogously also functions with only one coil and/or onerolling body (per coil). Through the use of multiple electrical coils,the flux density at critical points (coupling rod, sleeve) can bereduced, and the entire construction can be made thinner. It wouldhowever also be conceivable to generate the same torque with only one(long) coil and one (long) rolling body.

It is important for the coils to be fixedly fastened on the coupling rodand to thus be static relative thereto (or to the bodyshell in the caseof a door component). This facilitates the electrical connection. Thespindle nut is also static; only the spindle (and the ferromagneticsleeve therein) rotates—along with possibly also a few small parts suchas drilled nuts.

There may be bores in the coupling rod which run transversely or else ina zigzag pattern. These are possibilities for connecting the individualcoils to one another without affecting the raceway of the rollingbodies. It is also possible for an axial channel to be formed on thesurface of the coupling rod. Here, a ring can also be pushed (as racewayor sealing point) over such an axial channel. It is also possible toprovide an axial central bore with radial bores to the individual coils.

The question of whether the coils are laid out in series or parallel oreach connection is laid out individually is dependent on the usagesituation and the desired characteristics. All variants are possible. Itmay be advantageous for the coils to have different electromagneticcharacteristics. In particular, coils with the same shape/samedimensions may be wound differently (different wire thickness+number ofwindings, different material).

The coils may (though need not) have coil carriers. A coil carrier orcoil holder is not imperatively necessary; use may also be made of aircoils, or the coils may be wound directly onto the coupling rod (whichcan also be referred to as a shaft). Here, lateral delimitations (disks,stop rings) may be used instead of a coil carrier.

The coils may be potted (sealed) or may be open and then in contact withthe magnetorheological fluid (MRF). The coils may be threaded asfinished components onto the coupling rod, which is preferably ofcircular form, or may be wound directly on the coupling rod.

It is advantageous if a plug connector (plug) is situated on the coilcarrier (also referred to as coil holder) or a part of the carrier formssuch a plug connector (plug).

In addition to the coils or instead of a part of the coils, magneticallyhard material may also be part of the magnetic circuit, and thusgenerate a defined base torque without electrical current. Such amagnetically hard material is provided preferably in the region of thecoupling rod and/or of the sleeve. The magnetically hard material may bea permanent magnet, the permanent magnetic field of which can have adynamic field of a coil superposed thereon. Alternatively, remanence maybe used, where permanent magnetization of the material is set by meansof (short) electrical pulses.

An intermediate ring is preferably provided between adjacent magneticcircuits. Alternatively, use may also be made of two rolling bodieswithout an intermediate ring in between, or of one single, relativelylong rolling body. The relatively long rolling body is, at one end, partof one magnetic circuit and, at the other end, part of the othermagnetic circuit.

Grooves may be provided under the rolling bodies. Said grooves are notimperatively necessary. They however locally increase the flux densityand thus make it possible to transmit a higher torque radially at theinside.

(Rubber) rings may also be placed into the grooves in order to definethe position of the rolling bodies in the gap and force a rotation ofthe rolling bodies, because said rings prevent slippage on the innerdiameter. It is also possible for multiple grooves to be provided perrolling body.

The preferred (construction illustrated in the exemplary embodiment) hasthe advantage that, at one end, there is only one plain bearing/screw-inpart. The electrical connection is realized through the shaft in thedirection of the pivot axle.

Alternatively, the electrical connection may also be realized in thescrew-in part. The screw-in part may be fixedly connected to thecoupling rod (in order that the plug is static relative to the doorcomponent). The electrical connection may then be realized analogouslyto other components of the door (window regulator, loudspeakers,lighting, wing mirror adjustment means).

In particular, the screw-in part is also suitable for accommodating notonly the plug but also (simple) electronics. Here, the electronics mayalso include a sensor; said sensor is intended to determine the openingangle of a door. Here, the relative movement (rotation) of the spindleunit with respect to the coupling rod may be measured.

In one specific embodiment, a cylindrical coupling rod or a couplingtube is connected, non-rotatably about the longitudinal axis, to thebodyshell (A or B pillar). The rod end may however pivot, in theconnecting part, relative to the door (articulately mounted).

Between said cylinder part and the spindle inner side, there is fittedat least one magnetorheological transmission apparatus (an MRFwedge-type bearing element), wherein rolling bodies or ball bodies,electrical coils, stop disks and cables are used. On the outer side ofthe spindle, there is a multi-turn thread. This is operatively connectedto a non-rotating spindle nut by means of the thread turns. The spindlenut is mounted, preferably pivotably, in the vehicle door by means of abracket.

Depending on the electrical energization of the magnetorheologicaltransmission apparatus (“MRF wedge-type bearing”), the force that has tobe imparted in order for a longitudinal movement to take place/bepossible varies.

Here, use may also be made of a ball screw spindle, recirculating-ballspindle or coated spindle.

A frictionally locking connection is also possible.

The invention permits a simple design (low cost), wherein it is the aimto design an apparatus or a door component with rotary damper (doorpivoting brake) which can be produced as inexpensively as possible. Withsuch an apparatus, numerous functions are possible, such as, for examplein the case of a door component, stopping before hitting an obstruction,anti-pinch protection (finger, hand . . . ). Certain sensors are howeverrequired for this purpose (near-field detection). In most vehicles, suchsensors are not present or are of a quality or design which is notsufficient for the flawless door opening function. Thus, the numerouspossible functions of the adaptive door damper can then only be utilizedto a limited extent.

It is advantageous for available information items to be utilized suchthat an increased functional scope of the door component can thus beachieved. This means utilizing information items such as:

-   -   position of the vehicle in space (longitudinal or transverse        inclination; for example, a signal from airbag or ABS control        unit),    -   approaching pedestrian or cyclist (from the parking sensor),    -   door locked or not (lock sensor or contact between door and        bodyshell)    -   seat information (driver seated on the seat and disembarks; seat        contact from the airbag or the seat heater)    -   key information (customer is outside the automobile and wishes        to enter)

These data can be evaluated and assigned corresponding electricalcurrent values at the rotary damper. It is possible here to dispensewith “expensive electronics” in the conventional sense.

A constant electrical current plus the “MRF wedge-type bearing” may beused. In the case of a “constant electrical current” (during themovement of the door, the electrical current or the electrical currentintensity (amperes) is not varied), the “special” characteristic of theMRF wedge-type brake is utilized. That is to say, during movement, thebraking force decreases; said braking force is very high in a standstillstate. Accordingly, the door can be easily moved to the desired endposition by the driver. As soon as the door is left in a stationaryposition, the braking force automatically increases (wedge effect orwedge characteristic curve), and the door is fixed.

As an alternative to this, or also in combination, a rotary encoder inthe door hinge, a longitudinal encoder between door pillar and door, anear-field sensor (optical sensor which monitors the ambient environmentand/or the door movement) may be used for position detection.

A local sensor which determines the opening angle of the door offersmany advantages. There are numerous possibilities for directly measuringsaid opening angle or deriving it from linear or rotational movement (bypotentiometer, capacitively, inductively, magnetically etc.).

Example 1) Sensor on the pivot axle of the shaft: In a preferredsolution, measurement is performed using a potentiometer. This is aninexpensive solution, though robust potentiometers are required. It ishowever alternatively possible, at the same position, for a Hall sensor,for example, to (contactlessly) measure the spacing of a magnet or theflanks of a toothed gear.

Example 2) Sensor linear: The movement of the threaded spindle relativeto the spindle nut. Here, the existing tooth structure can be sensed,preferably by means of an encoder, which can also interpolate. In thisway, a relatively high resolution is possible, but an expensive sensoris also used.

Example 3) Sensor measures rotational movement in the screw-in part (ordrilled nut).

Advantage: a relatively high resolution owing to the pitch of thespindle unit (with the same physical solid measure). A fraction of onerotation at the pivot axle (example 1, <90°) thus yields for example 3complete rotations over the entire stroke. Additionally, the (at leastpartially protected) region within the screw-in part can moderate a partof the environmental conditions, resulting in lesser demands on thesensor construction.

Ideally as an encoder, possibly as a low-cost solution withoutinterpolation. Example optical encoder as forked light barrier, whichsenses a tooth structure connected to the spindle. For the “low-cost”attribute, it is expedient to utilize the greatest possible number ofsynergies. A sensor on the pivot axle probably requires a housing, aplug and a cable. In the worst case, also a circuit board with a pair ofadditional components (protective functions, signal preparation).

In the region of the screw-in part, the sensor could be part of a smallelectronics assembly (activation, connection of coils, plug connectionto the vehicle).

With regard to electronics: “constant electrical current” offers manyadvantages. It is possible for an existing control unit to perform theactivation of the doors, though the realization may be more complex thanimplementing a separate small activation means.

It is possible to use a control unit which is present which directlyactivates the actuator or multiple actuators. Since not only logiclevels are switched but a certain amount of power is also required, acorresponding control unit is necessary.

It is preferable for a minimal expenditure of “intelligence” to be used,entirely without a control unit, that is to say similarly to a windowregulator, for example the actuators have no considerable advantage overexisting systems.

In an existing/central control unit, it is possible to utilizesynergies, for example polarity reversal protection for the supply orelse a multi-channel switch (=IC with multiple switches) for allactuators.

This is expedient and offers numerous technical advantages.

A dedicated control unit is advantageous and permits dedicatedactivation for each actuator and ideally directly at or in the actuator.For example, in the region of the screw-in part, such that no housing isrequired (and no plug connector to the coils, because these can bedirectly soldered on). An advantage is that the activation of theactuator is possible directly with PWM, because a short connection tothe coils is possible and the construction is shielded by the housing. Aseparate control unit is furthermore advantageous if a sensor is alsointegrated. This can use common resources (supply, circuit board,protective circuit, plug connection).

A modular concept is possible; all that is required for operation ison/in the actuator, only a plug connection to the vehicle (supply).

The control unit can permit real-time closed-loop control of the doordamper using simple means; autonomous operation is possible with onesensor.

Global information can be exchanged via a bus (spatial position ofvehicle, obstruction . . . ). This permits a better coordination of thefunction and additional possibilities. Information items relating to thedoor damper can also be fed back to the vehicle (sensor, diagnosis . . .). LIN is expedient for such applications, though analogue controlvoltages, simple digital commands or more complex communication via bussystems are also conceivable.

A further variant is a combination in which a central control unit isused but the power electronics are at the actuator. Activation is thenpreferably performed without power (analog or digital).

If, in the case of constant electrical current, it is the intention tobe able to set only a small number of predefined electrical currentlevels, an interesting approach is to be able to individually switch thecoils. This functions in the manner of a heating fan: one heatingloop=half power, both heating loops, full power. On the other hand,multiple switches are required.

It is also possible to construct a closed-loop electrical currentcontroller which can output different electrical current intensities. Inthe simplest case, various switches with different series resistancesare sufficient. This approach has limitations with regard to energyefficiency and flexibility. Such a solution is highly dependent onexternal parameters (supply voltage, temperature . . . ). These can, inpart, be compensated (for example voltage stabilization), wherein theoutlay for this would however be greater than simply implementing asupply which can be controlled in continuously variable, closed-loopfashion.

A continuously variable electrical current output is possible. In thesimplest case, by means of a linear closed-loop controller, but here,energy that is not required is “lost as heat”. This could be acceptablein this usage situation because relatively low electrical current can beexpected (500 mA). The activation means must be able to drive themaximum electrical current even in the worst case.

Alternatively, a clocked/switched closed-loop electrical currentcontroller may be implemented. For this purpose, however, additionalcomponents (switches, inductances, capacitors are required).

By contrast to multiple electrical current stages which can be set bymeans of multiple switches, one switch suffices for the continuouslyvariable activation.

In summary:

1. Switch binary: on or off, 2 states per switch

With n switches 2{circumflex over ( )}n states: 2 switches for 4 stages,3 switches for 9 stages—but only if the stages can be switched in askillful manner.

2. Switch continuously variable: linear operation, linear closed-loopcontrol

The switch can assume any intermediate states, the resistance is of theswitch element is controlled such that the desired voltage/electricalcurrent/power prevails at the actuator. Energy that is not required is“lost as heat” in the switch.

3. Switch binary, fast clocking: PWM

Fast switching on and off controls the power prevailing, on average, atthe actuator. Frequency outside the perceptible range, additionalcomponents smooth the output signal (EMC).

It must be observed here that, instead of closed-loop electrical currentcontrol, it is very likely that closed-loop voltage control or open-loopvoltage control is also sufficient. The resistance of the coil does notchange to a great extent (only slightly owing to the temperature).Manufacturing tolerances are probably more critical. These can howeverbe specified, and/or a calibration can be performed after themanufacturing process.

The previous approaches are based on a switch which, in the activatedstates, closes the electrical current circuit and thus permits theelectrical current flow through the actuator. If the switch is openedwhile electrical current is flowing in the coil, a freewheeling diodeenables this to continue circulating. The electrical current is slowlydepleted by means of the resistances that are present.

For a fast load dump (electrical current back to zero), a full bridge isadvantageous. By means of this, the electrical current direction can bereversed, whereby the electrical current falls very quickly. For alow-cost solution, this approach is too complex, in particular becauseno further advantages can be attained from a reversal of the electricalcurrent direction.

Alternatively, the resistance in the freewheeling path may also beincreased by means of other elements (resistance, Zener diode . . . ).In this way, the losses upon switching off increase, the electricalcurrent falls more quickly.

Further advantages and features of the present invention will emergefrom the exemplary embodiments, which will be discussed below withreference to the appended figures.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 shows a highly schematic plan view of a motor vehicle with anapparatus with a rotary damper;

FIG. 2 shows an apparatus with a rotary damper in a perspective view;

FIG. 3 shows a plan view of the apparatus as per FIG. 2 ;

FIG. 4 shows a section through the apparatus as per FIG. 2 ;

FIG. 5 shows an enlarged detail from FIG. 4 ;

FIG. 6 shows a perspective view of another apparatus;

FIG. 7 shows a sectional diagrammatic sketch; and

FIG. 8 shows the force profile of an apparatus as per FIG. 2 or 6 .

DETAILED DESCRIPTION OF THE INVENTION

Here, FIG. 1 shows the use of the apparatus 50 according to theinvention as a door component 100 on a motor vehicle 200, and in thiscase a passenger car. The motor vehicle 200 is illustrated is in aschematic plan view from above. Here, two door devices 154 designed asdoors are provided on the motor vehicle 200. The doors are both situatedin the open position 103. Hatching is used to show one door in theclosed position 102.

To dampen the pivoting movement of the doors 154, door components 100are provided which each comprise a rotary damper 1. The door componentseach comprise attachment units 151 and 152, of which one is attached toa supporting structure of the motor vehicle 200, while the other isconnected to the door 154, such that a relative movement of theattachment units 151 and 152 occurs during an opening or closingmovement of the door 154. The attachment units 151 and 152 movelinearly. A conversion into a rotational movement occurs, which isdampened by the rotary damper 1 of the apparatus 50.

The apparatus 50 may be designed as a door component 100 and comprisethe rotary damper 1 and attachment units 151 and 152 and be used fordamping the rotational movement of doors and flaps on a motor vehicle200. The apparatus 50 may also be directly designed as a damper device50 and comprise the rotary damper 1 and attachment units 151 and 152 andbe used for damping rotational movements, or for example linearmovements, between the attachment units 151 and 152.

FIG. 2 shows a perspective illustration of the apparatus 50, wherein theapparatus 50 comprises a rotary damper 1.

The apparatus 50 may be designed as a damper device or else as a doorcomponent 100 and thus serves for use on the motor vehicle 200 from FIG.1 or for other uses.

The apparatus 50 comprises a first attachment unit 151 and a secondattachment units 152, which may be arranged at the opposite ends. It ishowever also possible, as shown in FIG. 2 , for the attachment unit 152not to be arranged or mounted at the physical end of the apparatus 50.

The apparatus 50 comprises a coupling rod 3, which projects into therotary damper 1. At the outer end of the coupling rod 3, there isprovided a pivot axle 24, pivotably about which the coupling rod 3 isreceived. The first attachment unit 151 is articulately mounted at thepivot axle 24. Here, on the attachment unit 151, there is formed afastening bore 26 which, in the case of use as a door component 100,serves for example for the fastening to a door pillar. An angle sensor23 (designed for example as a rotary encoder) may also be arranged atthe pivot axle 24.

The coupling rod may have any desired three-dimensional contour, that isto say need not be straight. This facilitates installation inconstricted space conditions.

The second attachment unit 152 is in this case arranged in the centralregion of the apparatus 50 and comprises a fastening bracket which isarranged so as to be pivotable about the pivot axle or the joint 25. Thebracket 20 surrounds the spindle unit 4, which is designed as a threadedspindle here.

FIG. 3 shows a plan view of the apparatus 50, in which it is possible tosee the second spindle unit 5, which in this case is designed as aspindle nut and which is in engagement with the first spindle unit 4.The spindle unit 4 is arranged fixedly in an axial direction on thecoupling rod 3. The threaded spindle 4 is however arranged rotatablyabout the coupling rod 3, such that, in the event of a relative axialdisplacement of the two attachment units 151 and 152 relative to oneanother, the spacing of the attachment units 151 and 152 changes, andtherefore the spindle nut 5 held rotationally fixedly on the attachmentunit 152 causes a rotational movement of the threaded spindle 4 aboutthe coupling rod 3. As a result, the spindle nut 5 can axiallydisplaceable on the threaded spindle 4, whereby for example an openingor closing of the door of a motor vehicle is made possible. The spindleunits 4 and 5 convert a linear movement into a rotational movement.

FIG. 4 shows a section through the apparatus 50, wherein the attachmentunit 151 is attached to the in this case left-hand end of the couplingrod 3.

The threaded spindle 4 is mounted rotatably about the coupling rod 3 atthe left-hand end by means of a bearing 7 designed as a rolling bearingand at the right-hand end by means of a bearing 37 designed as a plainbearing. The bearings 7 and 37 are arranged in the semicylindricalinterior space between the threaded spindle 4, which is of hollow form,and the coupling rod 3.

At one end, a threaded nut 12 is screwed onto the coupling rod in orderto fix the inner ring of the rolling bearing 7 in an axial direction.Correspondingly, a drilled nut 16 is screwed into the same end into thehollow threaded spindle 4 in order to axially fix the outer ring of therolling bearing 7.

Here, at the other end, a screw-in part 19 is screwed into the hollowend of the threaded spindle 4 and, there, completely closes the openingof the threaded spindle 4. The plain bearing 37 is in this case formedor inserted on the screw-in part 19.

Here, in the interior of the hollow spindle nut 5, there is inserted asleeve 17 which is rotationally conjointly connected, and for exampleadhesively bonded or fixed in positively locking fashion, to thethreaded spindle 4. The use of a sleeve 17 composed of a ferromagneticmaterial makes it possible for the threaded spindle 4 itself to beproduced for example from a plastic. This leads to a considerable weightsaving. Furthermore, in this way, self-lubrication of the threadregions, which engage into one another, of the spindle nuts 4 and 5 canbe achieved, such that the apparatus 50 can be operated withoutmaintenance.

Arranged adjacent to the rolling bearing 7 is a seal 13, which comprisesfor example a shaft sealing ring and which seals all gaps by way ofcontact. Since the coupling rod 3 is preferably composed of aferromagnetic material and for example a relatively soft steel, a race28 composed of a hardened or coated (for example hard chromium) materialis preferably applied to the coupling rod 3 in the region of the seal 13in order to prevent wear.

In the interior, a multiplicity of magnetic circuits is preferablyaccommodated in the cavity between the coupling rod 3 and the sleeve 17(if the threaded spindle is composed of plastic, for example) or theinner wall of the threaded spindle 4 (if this is composed of aferromagnetic material and no sleeve 17 is present) and the outersurface of the coupling rod 3. For this purpose, in thehollow-cylindrical interior space, electrical coils 9 are either wounddirectly onto the coupling rod 3 or are wound onto coil holders 11,which are subsequently pushed onto the coupling rod 3.

Adjacent to the electrical coils 9, preferably on each axial side, thereis accommodated a multiplicity of rotary bodies or rolling bodies 2, bymeans of which the magnetic field of the magnetic circuit is closed. Forexample, 8 or 10 rotary bodies 2 may for example be arranged so as to bedistributed over the circumference at one axial position.

FIG. 5 shows an enlarged detail from FIG. 4 , wherein, here, the profileof the magnetic field 10 or a field lines of a magnetic circuit is shownby way of example.

The magnetic field generated by the electrical coil 9 as magnetic fieldsource 8 runs through a portion of the sleeve 17 and passes through arotary body 2 arranged adjacent to the electrical coil 9 and enters thecoupling rod, which is composed of a likewise ferromagnetic material,and runs axially back to the next rotary body 2, where the magneticfield line enters again radially through a rotary body 2 and into thesleeve 17 and is closed there.

It is preferable for in each case two separate rotary body rows to beprovided between two axially adjacent coils. Multiple magnetic circuitsmay be provided which are axially spaced apart from one another. Eachmagnetic circuit may for example comprise two rows of rotary bodies,which are arranged, in each case to the right and to the left of anelectrical coil, so as to be distributed over the circumference.

It is however also possible for rotary bodies which are elongate in anaxial direction to be provided, such that one end of an elongatecylindrical rotary body is flowed through by the magnetic field of theelectrical coil 9 which is adjacent on one axial side, whereas the otherend of the cylindrical rotary body 2 is flowed through by the magneticfield of the next electrical coil 9.

Centrally in the interior of the coupling rod 3, there may be formed achannel 21 which comprises branching channels which run for example tothe individual electrical coils 9 in order to provide a targeted supplyof electrical current to the individual electrical coils 9.

It is possible for between rings 18 to be provided in each case betweenthe individual series of rotary bodies 2 in order to separate theindividual magnetic circuits from one another.

Also clearly visible in FIG. 5 is the external thread 14 of the threadedspindle 4, which is in engagement with the internal thread 15 of thespindle nut 5. The external thread need not have the same pitch over theentire length; different pitches and pitch regions are also possible.

FIG. 6 shows another embodiment of an apparatus 50 with a rotary damper1, wherein, in this case, too, a threaded spindle 4 which is rotatableon a coupling rod 3 is provided, which threaded spindle is in engagementwith a rotationally fixedly held spindle nut 5. The spindle nut 5 isheld on the fastening bracket 20. Attachment units 151 and 152 againserve for the fastening of the apparatus 50. In this case, too, theapparatus may be held so as to be pivotable about pivot axles 24 and afastening bolt 27.

At the attachment unit 152, or adjacent thereto, it is possible here tosee a motor 29, which can for example be supplied with electricalcurrent through the coupling rod 3. The motor 29 serves for activelyrotating the threaded spindle 4 and is itself held rotationally fixedlyon the fastening bracket 20. Here, in the fastening bracket 20, thereare formed grooves into which corresponding fingers of the motor 29engage such that the motor 29 is displaceable axially along thefastening bracket 20 but is held rotationally fixedly therein. In thisway, the motor 29 can be used to actively rotate the threaded spindle 4such that an active length variation of the apparatus 50 is alsopossible. In this way, in the case of use as a door component 100, it isfor example also possible for an automobile door to be actively orsemi-actively partially or completely open or closed (in guidedfashion).

Semi-active means that the electric motor assists (generates an activetorque) the manually guided movement for example of a door by a usersuch that, at all opening and closing angles, and in particular takinginto consideration different frictions, kinematic changes and spatialpositions (vehicle is obliquely inclined), similar actuating forces haveto be applied by the user (the user “guides” the door=guided door).Here, this semi-active mode can be assisted by means of the veryfast-switching brakes of the brake unit, which is manifest in particularpleasant haptic opening and/or closing and/or actuation. This isparticularly advantageous in an inclined position (on a gradient) whenthe door would automatically open owing to the force of gravity but hasto be closed in the opposite direction. Here, fast switching betweenbrake and drive must be performed in order to provide a good hapticfeel. Here, fast and haptic advantageously means preferably in a fewmilliseconds and in continuously variable fashion, in order that smoothtransitions are possible. Two-stage couplings (coupled/decoupled) leadto poor results (jerky movements and load peaks) which are not acceptedby vehicle manufacturers from the premium segment.

FIG. 7 shows a schematic diagrammatic sketch of the functioning of themagnetorheological transmission apparatus 40 with the basic principle ofthe rotary damper 1. This figure basically already appears in WO2017/001696 A1. The description in this regard, and the entire contentof WO 2017/001696 A1 is therefore also incorporated into the disclosureof the present invention.

FIG. 7 shows two components 32 and 33, the relative movement of which isto be damped, or influenced in targeted fashion, by means of thetransmission apparatus 40. For this purpose, in a gap 35 between thecomponents 32 and 33, there is arranged a multiplicity of rotary bodies2, which are embedded into a magnetorheological fluid 6. The rotarybodies 2 function as magnetic field concentrators, which, in thepresence of an applied magnetic field and a relative movement of thecomponents 32 and 33 with respect to one another, leads to a wedgeeffect, wherein wedge-like regions 46 are formed in which themagnetorheological particles collect and, by means of the wedge effect,effectively brake an onward rotation of the rotary bodies 2 and arelative movement of the components 32 and 33 with respect to oneanother.

Here, the free spacing 39 between the rotary body 2 and the surface ofthe components 32 and 33 is basically larger than a typical or averageor maximum particle diameter of a magnetorheological particle in themagnetorheological fluid. By means of this “MRF wedge effect”,considerably more intense influencing is achieved than would beexpected. This leads in particular to a high static force, which can beutilized as holding force.

The rotary dampers 1 shown here in the exemplary embodiments allfunction in accordance with this MRF wedge effect.

The high static force can be effectively utilized as a holding force andcan be advantageously utilized as shown in FIG. 8 , which illustratesthe force profile of the braking force of the magnetorheologicaltransmission apparatus 40 or of the rotary damper 1, versus therotational speed of the rotary bodies (and analogously also of therotatable spindle unit). It can be seen that, when the rotary body 2 isat a standstill, a very high braking force is generated. If the userovercomes the braking force that holds the door open, the braking forceconsiderably decreases with increasing speed even when the magneticfield continues to be applied, such that, even when the magnetic fieldis applied, the user can easily close the door after overcoming thesufficiently high holding force.

This effect has the result that, basically in any desired angleposition, a high holding force is generated, which the user can howeververy easily overcome in order to close the door. A very convenientfunction is thus provided.

The following is a summary list of reference numerals and thecorresponding structure used in the above description of the invention:

-   1 Rotary damper-   2 Rotary body, rolling body-   3 Coupling rod-   4 Spindle unit, threaded spindle-   5 Spindle unit, spindle nut-   6 Magnetorheological fluid-   7 Bearing-   8 Magnetic field source-   9 Electrical coil-   10 Magnetic field-   11 Coil holder-   12 Threaded nut-   13 Seal-   14 External thread-   15 Internal thread-   16 Drilled nut-   17 Sleeve-   18 Intermediate ring-   19 Screw-in part-   20 Fastening bracket-   21 Channel-   22 Fastening bore-   23 Angle sensor-   24 Pivot axle-   25 Joint-   26 Fastening bore-   27 Fastening bolt-   28 Race-   29 Motor-   30 Force profile-   32 Component-   33 Component-   34 Separate part-   35 Gap-   39 Free spacing-   40 Transmission apparatus-   42 Axis of rotation-   46 Wedge shape-   50 Apparatus-   100 Door component-   102 Closed position-   103 Open position-   151 Attachment unit-   152 Attachment unit-   154 Door device-   160 Sensor-   200 Motor Vehicle

The invention claimed is:
 1. A method for influencing a movement of apassenger door of a vehicle, the method comprising: providing a doorcomponent having a controllable damper device and two attachment unitsthat are movable relative to one another; providing two spindle unitsthat are in engagement with one another and disposed between the twoattachment units; providing a sensor and using the sensor to determine aposition of the passenger door relative to the vehicle; controlling amovement of the passenger door at least partially between a closedposition and an open position by a controlled actuation of a damperdevice and a motor for driving one of the spindle units with referenceto the relative position of the door determined by the sensor, tothereby achieve a guided door movement; and wherein one of said twoattachment units is connected to a supporting structure and another ofthe two attachment units is connected to the door, the spindle units area threaded spindle and a spindle nut, respectively, and the methodcomprises influencing a rotation of one of the spindle units with amagnetorheological transmission apparatus in order to influence themovement of the door, and the magnetorheological transmission apparatusis arranged radially within the first spindle unit.
 2. The methodaccording to claim 1, which comprises determining with the sensor anopening angle of the passenger door.
 3. The method according to claim 1,which comprises providing a near field sensor and acquiring with thenear field sensor information regarding an ambient environment in avicinity of the vehicle.
 4. The method according to claim 1, whichcomprises controlling the movement of the door by influencing a rotationmovement of one of the two spindle units with a magnetorheologicaltransmission apparatus.
 5. A method for influencing a movement of apassenger door of a vehicle, the method comprising: providing a doorcomponent having a controllable damper device and two attachment unitsthat are movable relative to one another; providing two spindle unitsthat are in engagement with one another and disposed between the twoattachment units; providing a sensor and using the sensor to determine aposition of the passenger door relative to the vehicle; and controllinga movement of the passenger door at least partially between a closedposition and an open position by a controlled actuation of a damperdevice and a motor for driving one of the spindle units with referenceto the relative position of the door determined by the sensor, tothereby achieve a guided door movement; and wherein one of said twoattachment units is connected to a supporting structure and another ofthe two attachment units is connected to the door, the spindle units area threaded spindle and a spindle nut, respectively, and the methodcomprises influencing a rotation of one of the spindle units with amagnetorheological transmission apparatus in order to influence themovement of the door, and wherein an annular cylindrical cavity isformed radially between a coupling rod and one of the spindle units, andthe magnetorheological transmission apparatus is disposed in thecylindrical cavity.
 6. The method according to claim 5, which comprisesdetermining with the sensor an opening angle of the passenger door. 7.The method according to claim 5, which comprises providing a near fieldsensor and acquiring with the near field sensor information regarding anambient environment in a vicinity of the vehicle.
 8. The methodaccording to claim 5, which comprises controlling the movement of thedoor by influencing a rotation movement of one of the two spindle unitswith a magnetorheological transmission apparatus.